Share-Based Compensation - Non-Cash Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-Based Compensation
Share-based compensation expense	$ 48,726	$ 16,879
Less: Share-based compensation expense attributable to non-controlling interests	360	0
Share-based compensation expense attributable to Biohaven Pharmaceutical Holding Company Ltd.	$ 48,366	16,879
Minimum
Share-Based Compensation
Requisite service period of award (in years)	3 years
Maximum
Share-Based Compensation
Requisite service period of award (in years)	4 years
Research and development expenses
Share-Based Compensation
Share-based compensation expense	$ 20,058	6,251
Selling, general and administrative expenses
Share-Based Compensation
Share-based compensation expense	$ 28,668	$ 10,628

Share-Based Compensation, Attributable To Noncontrolling Interest

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- Definition

Share-Based Compensation, Attributable To Parent

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of noncash expense for share-based payment arrangement.

+ References

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-Publisher FASB
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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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